[SOLVED] How to get process id - pid ?

[Lakshmipathi]

Say I want to run a command says top command,
I need to get process id after invoking it. something like

$pid= top
$echo $pid #pid of just invoked command

I don't want to use something like ps aux | grep top - since I have several top command running in parallel.

Thanks

[ngwasuma]

Say I want to run a command says top command,
I need to get process id after invoking it. something like

$pid= top
$echo $pid #pid of just invoked command

I don't want to use something like ps aux | grep top - since I have several top command running in parallel.

Thanks

What do you hope to achieve?

[Lakshmipathi]

I'm testing an application ...
start application1 -> get pid -> do some testing -> kill process using pid
start application2 -> get pid -> do some testing -> kill process using pid
application1,application2 ... are all same process created by same user.

[Rubberman]

On most distributions there is a command pidof which will return the process id's of named applications. If you want the pid of a background process when you start it, then you can use the shell variable $! which will return the pid of the last background process started in that shell. This is useful for shell scripts.

[Lakshmipathi]

you can use the shell variable $! which will return the pid of the last background process started in that shell. This is useful for shell scripts.

Spot on !! The $! will suit my requirements ...thanks Rubberman

[Rubberman]

Glad to be of service!